Apparatus and method of taking core samples of rock in bore holes



5. Sheets-Sheet 1 A. ANDERSON Filed Jan. 19, 1926' INVENTOR.

Julie 21, 1932.

nm'nflfis AND METHOD OF TAKING CORE SAMPLES OF nocx ,IN BORE HOLES II a? 39 L L3 as L l 24 fzs f'lz 2-71 June 21, 1932. A. ANDERSON 1,864,113

APPARATUS AND METHOD OF TAKING CORE SAMPLES OF ROCK IN BORE HOLES Filed Jan. 19, 926 5 Sheets-Sheet 2 MzmaQ/mw f/v VENTOR.

June 21, 1932. 1,864,113

APPARATUS AND METHOD OF TAKING CORE SAMPLES OF ROCK IN BORE HOLES A. ANDERSON Filed Jan. 19, 1926 5 Sheets-Sheet 3 m mu a r95 876ml. Jiezande rAndarJo n,

A ANDERSON 1,864,113

Q' THOD OF TAKING CORE SAMPLES OF ROCK IN BORE HOLES Filed Jan. 19,. 1926 5 Sheets-Sheet juera'ol: Abamnder Andero'o n v /lg 7/lllllfi l l HOLES ORE;

' emtor: rAruZerdO n,

June 21, 1932. ANDERSON APPARATUS ND METHODOF TAKING coma SAMPLES OF ROCK Filed Jan. 19, 1926 'IIIIIIIIII/IIIIIIIIIIfill/III!!! 1IlI/II/IIlI/IIIIIIIIIIIll I!lllllllltlllllllifvlllln .IlI'IIIl [ill] ?aten ted June 21, 1932 UNITED STATES PATENT OFFICE APPARATUS AND METHOD OF TAKING GORE SAMPLES OF ROCK IN BORE HOLES Application filed January 19, 1926. Serial No. 82,366.

This invention relates generally to a method and apparatus whereby substantially cylindrical cores may be obtained from the formations in a bore hole.

This invention relates particularly to a method and apparatus for obtaining-cores from within a bore hole for the purpose of determining the original position which the cores occupied when they formed a part of the solid rock. I

When Stratification planes of the formations can be clearly traced on an oriented core, and when the inclination of the hole from vertical and the direction of the inclination are also known, the trueamount and direction of the dip of the formations can be determined.

The invention is especially useful in connection with oil wells, since it is often necessary to know the direction in which the strata are inclined; because accumulations of oil are usually found at the apex of inclined formations. A determination of the direction in which the strata are dipping will in dicate the direction to the apex of the structure, or say the direction of the most valuable prospective oil land.

An object of this invention is to provide new and improved methods and apparatus for obtaining a core from the formations adjacent to the interior of a bore hole.

Another object of this invention is toprovide new and improved methods and apparatus specially adapted to be used in conjunction with known orienting methods and apparatus for the purpose of obtaining an oriented core from the formations adjacent to the interior of a bore hole.

Another'object of this invention is to provide new and improved methods and apparatus specially adapted to be used in conjunction with known bore hole survey methods and apparatus-for the purpose of obtaining a core from the formations adjacent to the' interior of a bore hole whereby the true amount and direction of dip of the formations may be determined.

Another object of this invention is to obtain a core sample from the side of a bore hole.

Other objects will appear from time to time in the course of the specification and claims.

When used for the purpose of taking oriented cores my apparatus is rigidly attached to the lower end of a section of pipe,

.and is lowered to the bottom of the bore by successive additions of further sections.

The apparatus is allowed to rest on the bottom of the bore and fluid is pumped under pressure through the line of pipe. The stream of fluid actuates a propeller or other hydraulic engine to rotate the core barrel and bit. The line of pipe does not rotate and remains stationary. The bit is pressed against the formations by gravity, by fluid impact and by hydraulic pressure. When a predetermined length of core has been cut the fluid outlet from the apparatus is automatically reduced. The induced rise in the pump pressure informs the operators of the completion of the core. Means are provided for locking the core barrel against any further rotation and when the locked core barrel is raised the core catcher engages and breaks off the core within it.

Means are also provided for preventing movement of the severed core within the core barrel from fluid pressure acting on its ends.

Efforts have been made to obtain oriented cores by means of the ordinary form of rotary core barrel, operated in conjunction with rotary oil well drilling equipment.

The core is cut as usual by rotating the string of pipe and core barrel.

The core is then broken off and means are employed to orient it.

In my opinion, based on the following actual experiments, all such efforts are of doubtful value in deep holes.

It can be demonstrated, and I have proven with suitable apparatus, that the top of a long string of pipe suspended in a bore hole can be rotated through degrees without rotating the bottom of the string at all.'

This means that the twisting torque applied to the top of the string was balanced by friction on the walls of the hole; so the twist did not get as far as the lower end of the string.

It is evident that the much greater torque the pipe and the core barrel will which has to be transmitted through the whole length of the string to operate the cutting head ofthe core barrel must twist the string of pipe very considerably.

When the cutting of the core is completed, and the pipe is at rest, the friction offered by the walls of the .hole will obviously prevent all this twist untwisting, for just the same reason that the friction prevented the twist from traveling along the pipe in my own experiment.

Now, when the weight is lifted off the cutting head of the core barrel and thepipe is raised to break oif the core, the friction at the lower end of the pipe will be greatly diminished. Consequently, the lower end of rotate.

The distance that it is necessary to raise the core barrel in order to break 0 the core is quite small; so it is highly probable that the core barrel is usually rotating at the moment that the core is broken off and retained within it.

Even then, all the twist is not yet. out of the pipe. The pipe must travel many feet up the hole before all the twist has rotated out at its lower end. The core barrel and contained core do not therefore actually come into a position of equilibrium with the string of pipe for some time after leaving bottom.

It is clear that in deep holes no orienting of cores cut in this way can be considered worth while.

Under the conditions described, there can be neither a dependable fixed relation between the original position of the core in the formations and its position relative to the core barrel, nor between the position of the core barrel at the time it caught the core and the line of pipe.

Comparing the above with the methods of my invention it will be noted that there are several important diiferences; my invention operates by fluid assingthrough the pipe-to which it is attac ed, but the pipe itse f is not rotated and no twist is induced in it.

After the core is cut (which fact is automat-ically indicated to the operators) the' core barrel in my apparatus is brought to rest, and is locked in definite permanent relation to the supporting pipe,-before the apparatus is raise formation.

There is another feature inherent in the ordinary method of core drilling with the rotary system in oil wells that merits consideration:

As much as 15 or 20 feet of core may sometimes be cut at one time. Close examination of this long core, after removal from the core barrel, will usually show it to be broken up into ieces.

It 1s obvious that only the last piece, at the bottom, actually in contact with the core to sever the core from the catcher, could ever be of use for orienting purposes.

The reason that the core is broken into pieces is, at least in part, due to the conditions in the hole.

The core barrel and the line of pipe to which it is attached are always considerably smaller than the diameter of the hole.

The pi e is never quite straight and the hole itsel is never quite straight.

The cutting head of the core barrel must rest with some weight on the bottom of the hole and consequently the pipe must obtain lateral support by bending enough to rest against the sides of the hole.

As a consequence of these unalterable conditions the axis of the core barrel describes a cone as it rotates: that is to say it wobbles.

So soon, therefore, as a piece of core gets long enough to project a distance upwards inside the core barrel the top of that piece of core will either come into contact with the wobbling wall of the core barrel, which will break it off, or the bulk of the core will receive a sufficient side squeeze from mud and dbris packed between it and the wobbling core bar rel to break it off.

One object of my invention is to provide a fluid-actuated core barrel adapted to be operated while attached to a line of pipe in a bore hole and designed to rotate accurately on the axis of the barrel for the purpose of cutting, a maximum amount of solid core without fracturing it.

I'shall mention only one more feature inherent in all core barrels operated in oil wells drilled by the rotary method.

During the cutting of a core with rotary oil well equipment, the downward feeding of the line of pipe and core barrel is accomplished by unwinding small successive lengths of drilling cable from time to time as the core-is cut.

Each successive lowering puts a certain weight on the cutting head. The cutting head then drills away the rock beneath it till the weight. on it is lessened and the line of pipe and-core barrel are then once more lowered.

It is obvious that the torque in the line of pipe becomes less as the weight on the cutting head is diminished when the rock beneath is drilled away.

The next sudden lowering again throws a reaitly increased weight onto the cutting ea j 4 The existin torque in the pipe is not suflicient to handTe the suddenly increased grip of the cutting head in the formations. Consequently the cutting head remains stationary 10,1 l-ld for a moment until the torque in the continv tionsdn hardness of the fgfmations cause a certain amount of chattering and jumping of the cutting head on the bottom of the hole and is another cause for fractures in the core.

If the core happened to fracture at its base just a moment before rotation of the barrel "was stopped, it is clear that that core would be useless for orienting purposes.

Comparing the above with the correspondi ng features of the present invention In place of a supporting line of hundreds, or thousands, offeet of irregularly rotating pipe, the core barrel in my apparatus is immediately supported within its stationary outer casing which rests directly on the rock surrounding the mouth of the core hole and the core barrel rotates in accurately aligned bearings mounted within this casing. N0 appreciable wobble is-possible.

The downward feed in the present apparatus is accomplished by the fixed Weight of the parts of the rotating core barrel and by hydraulic pressure, with a resulting nearly constant weight on the cutting bit.

The nature of the hydraulic means of rotation tends to damp out tendency towards jumping and generally provide smooth cutting action.

It is not intended to claim that my invention will out 15 or 20 feet of unbroken core.

The aim of my apparatus, when used for taking oriented cores, is to cut a predetermined length of unbroken core with maximum possible certaint By invention is il ustrated more or less diagrammatically in the accompanying drawings, wherein, like figures indicate like parts:

Fig. 1 and Fig. 1A taken together in the order mentioned form a longitudinal, part sectional, view of my apparatus.

Figs. 2, 3, 4, 5, 6, 7, 8, 9 and 10 are cross sections on the lines 2--2, 3-3, 4-4, 55, 6-6, 7'7, 88, 99 and 10-10 respectively.

Figs. 11 and 12 are, respectively, plan and elevational views, partly in section, showing the application of a simple form of radial sighting device applied to the casing of the apparatus, and useful in connectionwith the operation of orientingthe apparatus.

Fig. 13 is a view, looking in the radial direction along the sighting device, as shown in Figs. 11 and 12.

Figs. 14 and 15 are, respectively, plan and side elevation views of the application of a known form of telescope tangential sighting device that is secured to the casing in a known relative rotation position, by means of a removable clamp which constitutes a support for the telescope. This apparatus is used, in the orienting operation hereinafter described.

Fig. 16 is a sectional View, in elevation, showing a modified construction of the weight element 71 (shown in Fig. 1-,-A), in which this element is recessed centrally, to receive a suitable recording bore-hole survey instru- 71, with which the tube 70 is connected in driving relation.

Fig. 18 is a side elevation view, partly in section, showing another modification of mounting for recording survey instruments to be supported within the drill pipe, and arranged therein so as to not unduly impede the flow of the circulating fluid medium through the pipe.

Fig. 19 is a view, in elevation and partly in section,'of a modified form of fluid motor, with a geared drive through a longitudinally extended shaft to produce the desired rotation of the core cutting tool.

Fig. 20 is a view illustrating the manner of application of extensible springs to the outside of the drill pipe or casing, and preferably located adjacent the core cutting assembly for steadying the latter during the cutting operation, when the lower end of the casing is not permitted to rest on the bottom of the hole during the core cutting operation.

Fig. 21 is a view showing an angular threaded connection between the drill pipe 10 and the lower outer casing12L-Th1s view serves to illustrate, diagrammatically, that the outer casing element, which encloses and supports the core cutting and retaining apparatus of this invention, need not be in exact axial prolongation of the drill pipe 10.

.10 is the pipe extending to the mouth of the bore 11.

12 is the outer casing of my apparatus, connected rigidly to the pipe 10 by the coupling 13.

In its working position the lower end 14 rests on the bottom of the bore with weight on the teeth 15.

The casing 12 has holes 16 and 17 respec tively below and above the circular bracket 18.

The cylindrical sleeve 19 fits the inside of the casing 12 and rests on the upper side of the bracket '18. 1

This sleeve has holes corresponding in size and position to the holes 17.

The sleeve has two tapped holes 21 which receive fiat headed screws 22.

The screws 22 pass through slots 23 in the casing 12.

The sleeve 19 may be rotated. within 12 as far as the slots 23 will permit forthe purpose of partly closing the; holes 17 by causing the 24 with a bearing 25 and openings 26 to allow free passage for the fluid.

Similarly, a second bearing 27 is supported by a fixed substantially fluid-tight clrcular bracket 18. A round-ended-fixed pin 28 projects above the upper side of 18.

29 is an annular ring fixed inside the casing 12.

At least one curved spring 30, of flat section, lies partly within a slot in the outer, side of the ring 29: The upper end of this spring rests against the end of the slot at 31 and the springis secured by a screw 32.

The lower part of the spring below the securing screw normally lies against the face of the slot and is free to bend backwards linger downward pressure on its lower free en The lower end of the spring projects forward inside the line of the inner surface of the ring 29. I

A rivet retainer 33, is screwed into the side of the outer casing 12 and secured by a nut 34.

An axial hole 36 in the nose of 33 is a good fit for a rivet 35, preferably a copper rivet.

The head of the rivet is securely held against the inner countersunk end of the hole 36 by the flat-nosed set screw 37.

The rivet shown has been 'sheared off. Each new rivet reaches out as far as the bottom of one of'the rivet sockets 38.

One of these sockets is brought opposite the hole 36 before a new rivet is inserted.

The rotatable member, in this form, is divided into two'separate units.

The propeller 39 is shown as having our helical blades 40.

The boss 41 of the propeller is secured to the spindle 42 by the threaded portion 43, the nut 44 and a set screw 45.

' From the groove 46 to the shoulder47 the spindle 42 is square in cross section.

Below the shoulder 47 the part 48 is of circular section and ends in a round point 49.

The shoulder 50 of the spindle supports 20 roller cone 51. threaded roller cone 52 is screwed onto the threaded portion higher up on the spindle 42.

The cone 52 is retained in place by the keywasher 53 and keyway 54 and the nut 55.

Rollers 56 run between the cones 51, 52 and the female cone seats 57, 58.

The spindle 42 is carried between these roller bearings.

59 and 60 are grease retainers, with pack- .ing caps 61, 62 compressing the packing 63 and 64 against the spindle 42 to retain the grease which fills all the interior cavities between 59' and'60. i A hole 65 allows for equalization of pressure between the grease-filled cavities and the exterior fluid.

66 is afixed bracket having a boss 67 and fluid passages 68.

69 is a circular cap, having a square opening 70a making an easy fit for the square section of the spindle 42 which passes through it.

Four rivet sockets 38 are drilled in the exterior of the cap 69.

The circular cap 69 is screwed onto the upper end of the tube 70 and the spindle 42, ex-

tends downwards within the interior of the tube 70.

710; is a hole in the tube 70 for the purpose of equalizing fluid pressure.

71 is a solid generally cylindrical drilling weight axially bored and threaded at its upper end 72 to receive the lower end of the tube 70. The weight 71 is reduced in diameter at its lower end to form a shoulder 73. p

The extension 74 is externally threaded to engage the upper end of the core barrel 75.

A recess 76 communicates with the circulation holes 77.

7 8 is an annular plate. 79 is an annular disc. Both are removably held againstthe shoulder 73 by screws 80.

The diameter of the outer periphery of the plate 7 8 is only slightly less than the internal diameter of the fixed ring 29.

Near the periphery of the disc 79 is a circle of c osely spaced'holes 81. The holes 81 of the disc 79 are placed sufficiently close together (see Fig. 9) as to practically insure that the pin 38 will always register with one of the series. If desired, the lower ends of the drilled openings 81 may be slightly countersunk to guide pin 28 into correct registry osition.

Each of these holes is slightly larger in diameter than the in 28.

The radius of t e circle on which the holes are drilled corresponds to the distance between the axis of the pin 28 and the axis of the core barrel 75.

Circulation holes 77 admit flui barrel 75.

Attached to the lower end of the core barrel 75, is the core-retainer boss 82 housing the core retainer 83.

The hole 86 in the outer casing 12 provides asocket intended to receive and closely fit a projection formed on a radial or tangential sighting device of well known type.

The manner of use of a radial sightingdevice in the orienting operation is illustrated in Figs. 11-13. The outer casing 12 is provided with an opening or socket 86 (shown also in Fig. 1A), and into this socket there is inserted a projection 101 formed on the end of the sighting rod 100. The projection fits the socket 86 snugly and supports the sighting bar 100 in a direction that is radial with respect to the casing 12. Pins 103, 104,

which may be e. g. well known rifle or gun sights, serve as means by which the radial di -rection may be lined in, as seen in Fig. 13.

d to the core a A tangential sighting device, as illustrated in Figs. 14 and 15, may be used, in connection with the orienting operation, and the parts 105 and 106 are similar to the rod 100 and projection 101 of Figs. 11-13, above described. In the use of the device of Figs. 14 and 15, the line of sight X-X is parallel to the diameter Y which passes through the axis of the aligning opening or socket 86 in hole survey instrument within the apparatus,

embodying this invention, is illustrated in Figs. 16 and 17. In the first of these the weight element 71 is recessed axially as at 116, and a suitable recording survey instrument 117 is positioned therein as the apparatus is assembled. In Fig. 17, the survey apparatus 121 is shown housed within the lower end of the tube 70, and the apparatus extends, in part, into a recess in the upper part of the drilling weight 71. In both of these constructions the survey instrument is located closely adjacent the core to be cut, and is intended to be operative to give a record of inclination of the bore hole at approximately the depth from which the core is taken.

A further arrangement of means for sup porting a survey instrument within the casiIpg 12. or an extension thereof, is shown in In Fig. 18, a survey device 134 is supported within the casing 124 and between an upper bracket shown at 144 and a lower bracket at 138. In this construction, the survey device is provided at its lower end with a series of supporting pins, which enter appropriately spaced holes in the lower bracket 138, and at its upper end is provided with a stud-like projection which is supported in the central opening, in a spiderlike part of the upper bracket 144. The survey instrument is sup- 75 ported axially within the casing, and is arranged with relation to its support, so that its rotational position with respect thereto may be known; and also its support within the casing is designed to permit flow of the fluid circulating medium in the casing, without undue obstruction thereto.

The annular cuttingbit 84 screws into the member 82. and, in the form shown, is armed with diamonds 85.

Any other form of suitable cutting bit may be used.

Although the moving parts of my apparatus are shown as axially situated within the outer casing 12, these may be set at an angle thereto.

Although the outer casing 12 is shown as forming an axial prolongation of the pipe 10, may be attached to makean angle therewit Fig. 21 shows the outer casing 12 attached at an angle with the pipe 10 by the coupling 147 which has a beveled shoulder 148.

The operation of my apparatus is as follows:

Before lowering the apparatus into the hole, the set screw 37 is'withdrawn. One of the rivet sockets 38 is then brought opposite the hole 36 and a new rivet is thrust into the hole 36 with its point resting within the socket 38.

The set screw 37 is then driven home against the head of the rivet.

The rivet. is preferably made of copper or other similar easily sheared metal.

The rivet, substantially prevents all movements of the cap 69, and while thecap is retained in this position the bit 84 projects several inches beyond the lower end 14 of the outer tube 12.

The apparatus is now ready to be lowered into the well.

h 'llhe bit 84 first touches the bottom of the As soon as some weight is putonto the bit the rivet 35 is sheared and the bit is pushed up flush with the end of the casing 12.

When some weight has been placed on the teeth 15 the apparatus is ready for work.

Fluid pumped through the pipe 10 actuates the propeller and rotates the spindle 42.

The square lower portion of the spindle transmits its rotation to the cap 69 causing rotation of the core barrel and the bit 84.

The bit is pressed downwards bythe following separate agencies:

(a) The weight of the parts of apparatus to which it is attached, including drilling weight 71.

b) The force of the liquid stream impingin g on the upper side of the weight 71 and the plate 78.

(0) Excess pressure inside the outer casing 12 acting on the area of the core barrel A part of the fluid passes through the holes 77 and circulates downwards between the core and the core barrel 7 5 and bit 84, passing round the lower end of the bit 84 through theusual notches cut in the metal between the diamonds 85 and then upwards,'carr'ying the drill cuttings, between the outside of the rotating member and the walls of the core hole. This stream arrives in the chamber below 18 and finds exit through the holes 16 to join the main up-flowing stream coming outof the holes 17 To causea continuous positive circulation.

Ibo

of fluid into the holes 77 and around the bit I the fluid outlets 17.

By Varying the size of the plate 7 8 the downward pressure on the bit may be adjusted.

A similar alteration must be made in the ring 29 which must at all times closely fit the periphery of the plate 78.

As the bit penetrates the formations'the wholerotating element 7 0 moves downwards, the cap 69 slipping over the square part of the spindle 42.

By the time the downward drilling of the bit has lowered the plate 78 to the level of the fixed ring 29 the stream of fluid is shut off.

By the action of the pumps, the operators then know the exact amount of core that has been out.

When the plate 78 reaches the level of the top of the ring 29, the shoulder 47 (which is the point where the square section of; the spindle 42 ends) is just within the square hole in the cap 69.

The plate 78 has now practically stopped the flow of fluid past the propeller.

. Pump pressure is maintained to keep pressure on the plate 7 8 and hold the bit firmly on bottom.

The following events automatically occur as the pipe 10 is slowly raised; pump pressure being maintained 1. The plate 78 passes fixed ring 29.

2. Just before the plate 78 passes below the fixed ring the square hole in the cap 69 falls below the shoulder 47 of the square parts of the spindle 42.

3. As soon as the plate 78 is below the fixed ring the fluid again commences to flow and the propeller'again revolves.

4. As only the cylindrical section 48 of the spindle in now within the square hole 7 0a in the cap 69. the propeller rotates idly without causing rotation of the core barrel 75.

5. Thecirculation holes 77 are closed by passing inside the bearing 27.

6. The pin 28 enters one of the holes 81 of down through the the disc 7 9.

7. The disc 7 9"'is seated on the circular bracket 18.

8. The plate 7 8 is locked in its position on top of the bracket 18 by the spring 30.

As the plate passes beneath the ring 29 it presses the point of the spring 30 to one side. After the plate 78 passes it'the spring is released and forms a secure lock against upward movements of the plate.

Rotation of the'core barrel is prevented by the pin 28. The core,ba rrel is now secure against any kind of movement relative to the outer casing 12 and the orienting hole 86.

Further raising of the pipe 10 now raises the bit 84 ofl bottom. This causes the core retainer 83 to take hold of and break oil the core.

The pumps connection is pipe 10.

At the end of a run of this kind the fluid exterior to the pipe 10 is usually considerably heavier, owing to greater quantity of mud in suspension, than the fluid inside the pipe, in deep open holes. 1

Consequently, the severing of the pump connections is frequently accompanied by an outrush of fluid from the top of the pipe 10 due to the hydrostatic balancing of the exterior and interior fluid columns.

The excess exterior pressure, acting on the exterior area of the bearing 27 tends to push the core barrel upwards inside the outer casing 12 and release-the pin 28 from the are now stopped and the pump detached from the top of the disc 79.

movement of the core barrel can, however, take place. It is prevented by the spring 30 which resists any upward motion of the plate 78 and holds the disc 79 securely on thepin 28.

The excess exterior pressure also acts on the area of thelower end of the core within the core barrel.

The sealing of the circulation holes 7 7 within the bearing 27 prevents the core from being pushed upwards within the core barrel.

If these holes were not sealed, the core would be apt to be pushed violently upwards, and released from the core catcher 83.

This releasing and upward travel of the core inside the core barrel would be liable to cause rotation of the loose core within the barrel.

The hoisting of the apparatus to the surface is now commenced.

While the sections of the pipe 10 are being withdrawn from the bore, its fluid content escapes through the holes 17.

Escape of fluid from the pipe 10 may be prevented by increasing the depth of the ring 29 so that the plate 78 would seal all access to the openings 17 The spring catch 30 is then unnecessary because the weight of the fluid inside 10 holds the disc 79 securely in place on the pin 28.

From the explanations given above, it is clear thatat the moment of disconnecting pump connections from the pipe 10, this inethod of :holdin the disc 79 down on the pin 28 is not safe or use in deep open bores.

t is, however, a practical method under many conditions particularly in shallow bores, and I claim it as a new and separate method.

No upward WhGlLthG apparatus arrives on the derrick terior of the core barrel 75, part of which is projecting below the lower end 14 of the outer casing 12. j

The core barrel 75 is then carefully unscrewed from the drilling weight 74 and re moved from the apparatus.

The core barrel, may then conveniently be gripped in a vise in a horizontal position with the orienting mark upwards.

A rod may then be inserted into the mouth of the bit St to push the core out from the upper end of the core barrel. Care is taken not to rotate the core.

As the core comes out of the barrel a mark 15 is made along its upper side corresponding to the orienting mark on the outside of the core barrel.

The orienting methods and calculations supply the bearing of .the diameter of the 9 core which passes through this mark. Subsequent examination and measurement of stratification planes in the core, plus a knowledge of the inclination and direction of inclination of the'bore itself, will enable the true amount and direction of dip to be computed.

Instead of allowing the lower end of .the outer casing 12 to rest on the formations during operation, it may first be lowered, for

the purpose of shearing the rivet 35, and then raised enough to avoid resting on the formations.

This method is sometimes useful when it is diflicult to clear debris from the bottom of the hole.

Extensible springs may be attached to the outside of the casing 12, or to theexterior of the pipe 10, adjacent to the casing 12' to hold the apparatus steady within thebore during operation in this suspended position.

Referring to Fig. 20.

The extensible springs 149, are adapted to contact the walls of the bore 11 at 149A.

The springs are preferably attached by welding at 150 to the collars 151, 152 rotatably mounted on the pipe 10.

Fixed collars 153, 154 retain the spring assembly in position. a The rotatable spring assembly permits free rotation of the pipe within the bore. I

When my invention is used in conjunction with "apparatus and methods for orienting the pipe and when at the same time, a bore hole survey mechanism is also operated within the bore and supported by the same line of pipe, then the orientation methods employed .during'the lowering or raising of the line of rection of inclination of the core, and of the hole, may be obtained.

Iam aware that many changesmay be made in the design, construction and 0peration of an apparatus such as I have described without departing from the spirit of this invention.

In all the other models, the drilling weight 71 may also be substantially omitted, when the weight of the remaining parts or their proportions and the fluid pressures available, will admit. i

A re-arrangement of the parts of my apparatus shown in the drawings consists in making the square portion of the spindle 42 to form an integral part of the tube and project upwards inside a square axially situated hole through the propeller boss.

In this case the propeller boss drives the. spindle and the spindle passes through the hearings on which the propeller revolves.

Another form of my apparatus is constructed by substituting a gear wheel for the propeller blades in the above re-arranged form, mounting a propeller with a gear wheel on its spindle, on independent bearings, higher 11p inside the casing 12 and connecting the two units by gears mounted on an intermediate countershaft.

In Fig. 19, the above described propeller and gearing assembly is mounted for convenience inside a liner 170 which fits and is suitably secured inside the outer casing 12. In Fig. 19: 171 is a propeller, rotatably supported on the sh aft 171A between the spiders 172 and 173 and having a gear 174 attached near the lower end of the shaft. The gear 174 transmits motion to the gear 17 8 through the members 175, 176 and 177. The gear 178 is ri idly attached to the cylindrical member 179 lying within the bearing 179A formed in the spider 180.

The spindle 42 of through a square'opening 181 in the member 179 andreceives rotary motion therefrom.

In the apparatus which I have shown in the drawings, the lower part of the spindle Fig. projects upwards 42 is of square section, but may have a cross section with the form of a toothed gear wheel or any other suitable cross section. The lower end of the spindle 42, as shown in Fig. 19, is rectangular in cross section, and in this figure is broken away from its lower-most part, the illustrated shading of the element showing its square or rectangular cross-section.

The cutting bit, core catcher and core barrel which I have shown, are of known types. Any other suitable known types may be substituted. I

When the core barrel is locked in position, the lower end of the spring 30 rests on the top of the plate 78.

By cutting closely-spaced vertical grooves around the periphery of the drilling weight 71, adjacent to the top of the plate 78, and suitably shaping the point of the spring 30, the said spring might also perform the func- 18, and the size of theseopenings may be regulated by a flat annular disc movably attached underneath that part of the bracket. The annular disc is provided with holes corresponding to the outlet holes in the bracket.

One or two short studs, projecting upwards from the top of the bracket, prevent the disc 79 from seating on it, and provide exit space for the fluid beneath the disc 79.

The position of the ring 29 must be moved upwards by an amount equal to the length of the projecting studs, for the purpose of maintaining a correct relation between the locking spring 30 and the top of the plate 78.

Many other changes in design and arrangement of the parts of my apparatus can similarly be made without departing from the spirit and purpose of my invention.

WhatI claim and desire to secure by Letters Patent is 1. A fluid actuated apparatus for taking cores from the formations adjacent to the interior of a bore hole, comprising an outer casing adapted to be connected with a fluid supply pipe, an elongated driving member rotatably supported within the casing, and a fluid actuated propeller for rotating said member, and independently movable core barrel unit supported within said casing and connected with the driving member to be rotated thereby, the said unit comprising a core barrel, a core bit, core retaining means, and a telescopic connection with the said driving member for rotating the core barrel unit without imparting axial thrust thereto.

2. ;In a fluid actuated apparatus for taking. cores from the formations adjacent to the interior of a bore hole, an outer casing adapted to be attached to a fluid supply pipe, an actuating member and an elongated driving member rotatably mounted within said casing, said elongated driving member adapted to'be rotated by said actuating member, a core barrel unit mounted for rotational and longit-udinal movement substantially withinsaid outer casing, said core barrel unit comprising acore barrel, and associated means whereby the rotational movement of said elongated driving member may betransmitted to said core barrel: means for impeding the stream of actuating fluid for the purpose of providingindication of a pre-determined. amount of penetration of the core barrel within the strata; said means comprising: an enlargement formed on the core barrel unit in combination with an opening formed within said outer casing, said core barrel unit being adapted by a pre-determined longitudinal movement to bring said enlargement into asso'ciation with said circular opening to impedesaid stream of actuating fluid.

3. In a fluid actuated apparatus "for taking cores from the formations adjacent to the interior of a bore hole, an outer casing adapted to be attached to a fluid supply pipe, an actu outer casing, said core barrel unit comprising a core barrel, and associated means whereby the rotational movement of said elongated driving member may be transmitted to said core barrel: means for locking the core barrel to restrain it from longitudinal movement within its bearings, said means comprising the combination of a fixed abutment and a locking member movably held to project Within the downward path of an actuating member of said core barrel unit and so positioned that said locking member engages said actuating member after a pre-determined-longitudinal movementof said core barreland thereafter substantially prevents longitudinal movement of the core barrel within said outer casing.

4. A fluid actuated apparatus for taking cores from the formations adjacent to the interior of a bore hole comprising an outer casing adapted to be attached to a fluid supply pipe, an actuating member and an elongated driving member rotatably mounted within said casing, said elongated driving member adapted to be rotated by said actuating member, a core barrel unit mounted-for rotational and longitudinal movement substantially within said outer casing, said core barrel unit comprising a core barrel and associated means whereby the rotational movement of said elongated driving member may be transmitted to said core barrel, and means for preventing rotation of the core barrel within said outercasing, said means comprising in combination a male member and a recess member, one member of said combination being formed upon a member of said outer casing and the other member being formed upona member of said core barrel unit, said male member being adapted, after -a pre-determined longitudinal movement of stantially within said outer casing, said core barrel unit comprising a core barrel and associated means whereby the rotational movement of said elongated driving member may be transmitted to said core barrel, and means for causing a difference in pressure between the interior and exterior of the outer casing for the purpose of forcing a portion of the stream of actuating fluid to enter the core barrel from the interior of the outer casing and thereafter circulate past the cutting face of the core bit, said means comprising in combination, a substantially water-tight fluid chamber within the outer casing of the apparatus extending from the interior of the outer casing to and around one of the bearin s of the core barrel unit, a fluid outlet of suitably limited area, and an opening communicating between said chamber and the interior of the core barrel.

6. In the apparatus and combination of claim 5 means for regulating the amount of fluid passed through the core barrel, said means comprising a member movably mounted upon a member of said outer casing and adapted to regulate the area of the fluid outlet therefrom.

7. In combination with the invention defined in claim 1, means for causing pressure between the core bit and the formations said means comprising, in combination, a part of the weight of said core barrel unit, fluid pressure acting within said outer casing upon a part of the area of said core barrel and pressure resulting from the movement of fluid against a part of said core barrel unit, said pressure between said core bit and said formations being independent of the weight of said outer casing.

8. Apparatus for taking cores from earth formations contiguous to a boring comprising in combination a tubular casing to be lowered into a bore hole and to remain stationary during the core cutting operation, a rotary core cutting tool and motor for operating the same supported within the casing, means for operating the tool to cut a core of redetermined length, and means for retaining the cut core and the cutting tool fixed against rotation relative to the casing upon completion of the core cutting operatlon.

9. Apparatus for taking cores from earth formations contiguous to a boring comprising in combination a tubular casing to be lowered into a bore hole and to remain stationary during the core cutting operatlon, a rotary core cutting tool and motor for pperating the same supported wlthln the casing, a severable connection between the rotary element and the tubular casing that is adapted to be automatically broken by movement of the cutting tool relative to the casing, means for operating the tool to cut a core of predetermined length, and means for retaining the cut core and the cutting tool-fixed agalnst rotation relative to the casing upon comple- I .ered into a bore hole and supported at rest therein to serve as a fluid conductor, a rotary core cutting tool and fluid operated motor for turning the same, the tool and motor comprising a unit that is arranged substantially axially of, and within the said casing, a support for the motor fixed to the inner wall of the casing, a drive connection between the motor and tool which permits axial advance of the tool relative to the motor as the core is cut, and fluid pressure means supplied through the casing for operating the motor to cut a core of predetermined length, and means automatically effective to discontinue the cutting operation of the tool when the extent of the cut core equals the predetermined length.

11. Apparatus for taking cores from earth formations contiguous to a boring comprising in combination a tubular casing to be lowered into a bore hole and supported at rest therein to serve as a fluid conductor, a rotary core cutting tool and fluid operated motor for turning the same, the tool and motor comprising a unit that is arranged substantially axially of, and within the said casing, a support for the motor secured .to the inner wall of the casing, a drive connection between the motor and tool which permits axial advance of the tool as the core is cut, and fluid pressure means supplied through the casing for operating the motor to cut a core of predetermined length, means automatically effective to discontinue the cutting operation of the tool when the extent of the cut core equals the predetermined length,

and means secured to the casing for engaging and positively holding the cutting tool and the cut core against rotation relative to the casing upon completion of the core cutting operation.

12. -A core cutting tool su ported within a tubular casing and arrange to beoperated by fluid pressure supplied through the casing, the cutting tool comprising a hollow core barrel and a cutting bit, and means. effective.

to regulate the pressure exerted by the operating fluid on the core as it is cut;

13. Apparatus for taking cores from earth formations contiguous to a boring comprising in combination a tubular casing to be lowered into a bore hole and supported at rest therein, a rotary core cutting tool, and a motor for operating the same, the tool and motor being supported within the casing, a bore hole survey instrument capable of measuring the inclination and direction of inclination of the bore hole at any point along its length also supported within the casing and in a fixed position relative to the casing, means for operating the tool to cut a core means I orienting the said core barrel.

15. In apparatus for taking oriented cores from formations adjacent the interior of a bore hole, the combination including an outer casing adapted to be attached to a line of pipe, a core barrel, a core bit and operating means therefor supported within the outer casing, a bore hole survey device also suported and arranged within the outer casing or operation at the approximate level of the core to be cut, and means associated with the outer casing to cooperate with aligning devices for orienting the said core barrel.

16. Apparatus for'taking cores from earth formations contiguous to a boring comprising in combination a tubular casing to be lowered into a bore hole and to remain stationary during the core cutting operation, a rotary core cutting tool and motor for operating the same supported within the casing, means for operating the tool to cut a core of predetermined length, an extensible driving connection between the motor and tool which permits feed of the cutting tool into the earth formation as the core is being out, means for applying pressure to the cutting tool axially thereof, and means fixed to the easing for engaging and holding the cutting tool against both rotational and longitudinal movement upon completion of the core cutting operation.

1 Apparatus for taking cores from earth formationscontiguous to a boring compris ing in combination a tubular casing to be lowered into a bore hole and to remain stationary during the core cutting operation, a rotary core cutting tool and motor for operating the same supported within the easing, means for operating the tool to cut a core of predetermined length, a telescopic driving connection between the motor and tool to permit feed of the cutting tool-without axial thrust from the operating motor, means including a weight element for applying pressure axially of the cutting tool. .and'

' means secured to the casing for positively engaging and holding the cutting tool and the cut core against both rotational and longitudinal movement upon completion of the core cutting operation.

18. Apparatus for taking cores from-earth formations contiguous to a boring compris-- ing in combination a tubular casing to be lowered into a bore hole and to remain stathe motor, a core barrel with a tionary during the core cutting operation, a rotary core cutting tool and motor for operating the same supported within the casing, means for operating the tool to cut a core of predetermined length, including a driving connection between the motor and tool permitting independent feed of the cutting tool into the earth formation as the core is being cut andwhich connection is automatically interrupted when a core of predetermined length has been cut, and positive interengaging means between the casing and the cutting tool, effective at the end of the cutting operation to engage and retain the cutting tool and the cut core in a fixed position relative to the casing' 19. A core cutting assembly comprising a fluid motor device supported within a casing to be lowered into a bore hole, conducting means for fluid to and from the motor, and passagesto regulate the flow of fluid beyond the motor, a corebarrel with a cutting tool arranged to be driven bythe motor, and cooperative means between the core barrel and the casing operative after a predetermined length of core has been cut, to control the flow of fluid beyond the motor.

20. A core cutting assembly comprising a fluid motor device supported within a casing to be lowered into a bore hole, conducting means for fluid to and from the motor, and passages to regulate-the flow of fluid beyond the motor, a core barrel with a cutting tool arranged to be driven by the motor, and cooperative means between the core barrel and the casing operative after a predetermined length of core has been out, to control the flow of fluid beyond the motor, and to lock the core barrel against movement relative to the casing. i

21. A core cutting assembly comprising a fluid motor device supported within a casing to be lowered into a bore hole, conducting means for fluid to and from the motor, and passages to regulate the flow of fluid beyond cutting tool arranged to be driven by the motor, passages to admit fluid to the upper end of the core barrel and a sleeve element fixed to the casing to close said last named passages when the barrel has completed its cutting stroke, and means connected with the core barrel, operative after a predetermined length of corearranged to be driven by the motor, passages to admit'fluid to the upper end of the core barrel during the cutting o eration of the tool, and means effective a ter a predeter mined length of core has been cut to close the said fluid passages, and discontinue fluid circulation'through the core barrel.

23. Fluid actuated apparatus for drilling in a bore hole comprising a tubular casing adapted to be passed. into and moved along the bore and connected with a source of fluid supply, the said casing serving as a conductor for the fluid supply, a driving member rotatably supported within the casing and adapted to be held against axial movement in the bore during drilling, a bladed propeller actuated by fluid conducted along the casing and operatively connected to rotate the driving member, a drilling tool rotatably supported within said casing and a sliding connection between the driving member and drilling tool for rotating the latter without imparting axial thrust thereto in the drilling operation.

24. The method of taking oriented cores from earth formations adjacent bore holes, comprising the steps of cutting a core at a desired level in the bore, determining the inclination of the cut core in situ, breaking the core away from the earth. formation, and raising the core along the bore with the 'cutting tnol maintained against movement relative to its supporting means.

25. In apparatus for taking a core adja cent the interior of a bore hole comprising a fluid conductor to be lowered into the bore, a rotary core cutting tool supported thereby and mounted for rotation and longitudinal movement relative thereto, means for producing said rotation and longitudinal movement of the tool, and means effective to engage and hold the cutting tool against all movement relative to the said conductor when a core of predetermined lengthhas been cut.

In testimony whereof, I afiix my signature. I

ALEXANDER ANDERSON. 

